it sounds like the stomach virus. i had it and lost 7 pounds. i couldn't keep anything down,, sometimes not even a sprite. i had it for about 10 days. also, maybe you have sominela. you can get it from raw eggs. i would go see a doctor though, just to make sure. but if it is just a stomach virus, you will just have to let it run it's course.
hope this helps!! get well soon! =]]